When fuel tanks go bad

Reading about bad fuel tanks, especially fighterpilots impressive removal of a bad tank has me all paranoid. How do you know what kind of shape your tanks are in? Mine have no known issues, but what I don't know, I don't know. How does a bad tank present itself? I'm not even sure what mine are made of....

I don't know. How does a bad tank present itself?

IF you are changing fuel filters in very short intervals , its either the tank, or the fuel it contains.

Look on the outside of the changed filter.

Slyme like snot is "bugs in the fuel", kill the bugs.

Black covering fairly thick is asphaltine , clumped old fuel , use the boat to empty the tank.

Rusty metal is the interior of the fuel tank.Check with a magnet.

FF

Mr. "B": Saw your request on face book but didn't recognize the name so worried about spam etc. Anyway, in our case it was tough to know it was leaking. The PO said it was leaking. Oil "diaper" showed red/pink color at the inboard/aft end of tank. Even when we took it out we couldn't find the leak by visual inspection. The aforementioned corner was the low spot on the tank platform so the weepage came down to that corner. Since the PO had replumbed to the other tank I assumed the tank was empty, but when we went to cut it out it had 30 gal. of fuel still in it. The leak was actually a weep it was so slow.

Our tank was aluminum so no rust. There was some surface corrosion on the out side, with some dark stain areas here and there. It also had a drain valve at the lower corner that had been worked on by brazing etc. That may have been the leak but couldn't discern that. If you can figure out the area, to where the fuel would migrate, you could put a couple of oil pads in that area an check for color now an then. It isn't like the tank suddenly split and fuel poured out. Good luck. FP

Also look on the top of the tank, this is where water infiltrating from leaking decks will most likely cause some dammage.

Metal or plastic or fiberglass... should be easy to determine. Very likely it’s metal. Magnet tells you if it’s steel. “Very light” scratch with sharp metal object (knife point and strong light for viewing) should tell if the metal is SS or aluminum, by color and hardness. Monel is also very hard; it’s slightly darker than stainless with the slightest hint of copper color depending on the alloy.

Soltron fuel additive: http://www.navstore.com/soltron.aspx
How to Install an Aluminum Fuel Tank, by David Pascoe http://www.yachtsurvey.com/fueltank.htm

Tanks usually give plenty of warning signs as stated above, and if the do start to leak they usually will drip/weep which will give you some time to react. Being the eagle tanks are 34 years old made of mild steel I keep them about ½ full so there is enough room in the other tanks if one starts to leak. Also polish/clean the fuel, use additives, and try to turn the fuel every 1 to 2 years.

Fuel tanks are not usually made of SS but mild steel as SS needs to breath, hard to weld, heavy and expensive. Aluminum is usually used when replacing tanks which I don’t think is as good as mild steel. If the Eagle tanks go I plan on replacing with multi smaller plastic tanks and usng the larger old tanks as frame work for the new tanks.

Anyway if you are concern then take some positive action.

I would look a the top of the tank around the fill hose for water or rust. Check seams for wet spots with paper towel and use your nose. good luck

P/F- love the new avatar

Phil Fill said:

Tanks usually give plenty of warning signs as stated above, and if the do start to leak they usually will drip/weep which will give you some time to react. Being the eagle tanks are 34 years old made of mild steel I keep them about ½ full so there is enough room in the other tanks if one starts to leak. Also polish/clean the fuel, use additives, and try to turn the fuel every 1 to 2 years.

Fuel tanks are not usually made of SS but mild steel as SS needs to breath, hard to weld, heavy and expensive. Aluminum is usually used when replacing tanks which I don’t think is as good as mild steel. If the Eagle tanks go I plan on replacing with multi smaller plastic tanks and usng the larger old tanks as frame work for the new tanks.

Anyway if you are concern then take some positive action.

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Mine were foamed in aluminum...not a good idea because any water getting between the two will cause a reaction eventually leading to possible perforation. Keep 'em dry and you won't have problems from the outside in.
One More Time Around: Tankectomy

New aluminum tank is from speedytanks.com -- great service.

My 'temporary' tank was a plastic Moeller.




Foaming in plastic tanks is not recommended and aluminum was cheaper, not to mention the custom plastic tank people didn't seem to really want my business.

I see the Land-n-Sea Jeff. I remember a fellow in Juneau Alaska that had one. He was living aboard in the winter w single digit tenps a lot of the time and only had a small electric heater. It was nice and warm and dry in his boat. I remember he said the whole boat had lots of foam insulation in the cabin and hull. Looked like a well built boat. 28' as I recall.

Yes it is 28' and there foam in every void... 2" between the roof and liner, same for the hull and liner; enough foam that it's billed as unsinkable. Mine sleeps 7 inside (2 more on flybridge) and is remarkably well behaved behind the van on the road. I even splash her solo.
One More Time Around: Introduction

I'm looking at a 36' Albin. The deck fill for the tanks come down the outside edge of each tank then make a 90 degree turn into the side of the tank which protects the top of the tanks. The tanks are covered with some kind of thick insulation. Any idea how to check these tanks sides or bottoms?

"Foaming in plastic tanks is not recommended"

Most boat Mfg do foam in the tanks , done properly its excellent .

The reason it had problems is plastic tanks grow after contact with fuel.

So a builder has to place the tank, fill it with fuel ,wait a day or two, then foam it in place .

Big PIA where every second of employee time reduces the boat assemblers bottom line.'

For me MONEL is the std , but plastic would be fine if the sizes were close enough.'

FF